Fickle weather has forced organisers to cancel multiple WA festivals that were planned to take place on Monday, including a free event in Fremantle that was to be Perth’s main celebration.

Organisers Celebrate WA made the decision a day in advance due to the squally conditions engulfing the entire southwest of the State on Sunday, and forecasts for worsening weather that have included warnings for possible tornadoes and flash flooding.

Events in Albany, Kalgoorlie and Fremantle have been cancelled or postponed, leaving Geraldton as the only centre holding official celebrations on Monday.

“Strong winds are making it impossible to safely bump in the event, and conditions are not expected to improve sufficiently for a public event of this scale to proceed safely,” a statement on behalf of Celebrate WA read.

“The safety of patrons, performers, artists, vendors, staff, volunteers and event partners is always the overriding priority.”

Geraldton’s free event will feature local musicians Karloo Rockers bringing their blend of rock, reggae and country to the stage, cultural performances, archery and rope course fun, animal encounters and children’s activities.

Other regional towns and cities will host similar festivities in the coming weeks, including Broome, Newman, Port Hedland, Karratha and Carnarvon.

Fremantle’s free event was to be held around the fishing boat harbour and Bathers Beach, with live entertainment, cultural experiences, family fun and spectacular performances throughout the day.

The State’s major celebration in Burswood had already been pushed to November to avoid this scenario of poor weather cancelling the party.